Microalgae as a potential sustainable solution to environment health

Cyanobacteria such as Spirulina platensis secretes numerous biomolecules while consuming CO2 for photosynthesis which can reduce the environmental pollution as it can also be grown in wastewater. These biomolecules can be further processed in numerous pathways such as feed, fuel, pharmaceuticals, and nutraceuticals. This study aims to screen the potential molecular mechanisms of pigments from cyanobacteria as antidiabetic type-2 candidates through molecular docking. The activities of the test compounds were compared to commercial diabetic drugs, such as acarbose, linagliptin and polydatin. The results indicated that the binding affinity of pheophytin, 0-carotene, and phycocyanobilin to alpha-amylase were 0.4, 2, and 2.6 kcal/mol higher than that of acarbose with alpha-amylase. Binding affinity between pheophytin, 0-carotene, and phycocyanobilin with alpha-glucosidase were found to be comparable, which resulted 1.2, and 1.6 kcal/mol higher than that of acarbose with alpha-glucosidase. Meanwhile, binding activity of 0-carotene and phycocyanobilin with DPP-IV were 0.5 and 0.3 kcal/mol higher than that of linagliptin with DPP-IV, whereas pheophytin, 0-carotene, and phycocyanobilin with Glucose-6-phosphate dehydrogenase (G6PD) were 0.2, 1, and 1.4 kcal/mol higher from that of polydatin with G6PD. Moreover, pheophytin, 0-carotene and phycocyanobilin were likely to inhibit alpha-amylase, alpha-glucosidase, and DPP-IV competitively, while uncompetitively for G6PD. Thus, the integration of molecular docking and experimental approach, such as in vitro and in vivo studies may greatly improve the discovery of true bioactive compounds in cyanobacteria for type 2 diabetes mellitus drugs and treatments.